public class EnumDemo {     enum Color{     RED(3),BLUE(5),BLACK(8),YELLOW(13),GREEN(28);          private int colorValue;     private Color(int rv){     this.colorValue=rv;       }   private int getColorValue(){return colorValue;}   private int value(){return ordinal()+1;}
}          public static void main(String[] args) { for(Color s : Color.values()) {     //enum的values()返回一个数组，这里就是Seasons[]     System.out.println(s.value()+":"+s.name()+"="+s.getColorValue());     }     }
}   

    /*** Returns the ordinal of this enumeration constant (its position* in its enum declaration, where the initial constant is assigned* an ordinal of zero).** Most programmers will have no use for this method.  It is* designed for use by sophisticated enum-based data structures, such* as {@link java.util.EnumSet} and {@link java.util.EnumMap}.** @return the ordinal of this enumeration constant*/public final int ordinal() {return ordinal;}

import java.util.*;public enum Phase {SOLID, LIQUID, GAS;public enum Transition {MELT(SOLID, LIQUID), FREEZE(LIQUID, SOLID), BOIL(LIQUID, GAS), CONDENSE(GAS, LIQUID), SUBLIME(SOLID, GAS), DEPOSIT(GAS, SOLID);private final Phase src;private final Phase dst;Transition(Phase src, Phase dst) {this.src = src;this.dst = dst;}private static final Map<Phase, Map<Phase, Transition>> m = new EnumMap<Phase, Map<Phase, Transition>>(Phase.class);static {for (Phase p : Phase.values())m.put(p, new EnumMap<Phase, Transition>(Phase.class));for (Transition trans : Transition.values())m.get(trans.src).put(trans.dst, trans);}public static Transition from(Phase src, Phase dst) {return m.get(src).get(dst);}}public static void main(String[] args) {for (Phase src : Phase.values())for (Phase dst : Phase.values())if (src != dst)System.out.printf("%s to %s : %s %n", src, dst,Transition.from(src, dst));}
}